Locking and setting device



Nov. 27, 1945 J. T. PHHPF'S LOCKING AND SETTING DEVICE Filed Feb. 9,1945 2 Sheets-Sheet 1 [HY/EJ777751? July? IPHZ U UE Nov, 27,, 1945.

J. T. PHIPPS 2 3 LQCKING AND SETTING DEVICE Filed Feb. 9, 1945 2Sheets-Sheet 2 I17 V5.27 fur Jab]? YFPbJP UE Patented Nov. 27, 1945LOCKING AND SETTING DEVICE John T. Phipps, Whittier, CaliL, assignor, bymesne assignments, to Vernon Tool Co. Ltd., Alhambra, Calit acorporation of California Application February 9, 1945, Serial No.577,117

This invention relates to oil well tools, and more particularly tolocking and setting devices. This application is a continuation in partof my previously filed application, Ser. No. 480,121, filed March 22,1943.

In the operation of various oil well tools, it is common practice tomount the tools on a string of pipe threaded together at joints. Varioustools have been designed to be manipulated by the movement of the drillstring but in many instances the operation of these tools and therelease or locking of the tools is brought about by rotation of thedrill string. If the drill string is rotated in one direction thethreaded joints will be tightened, but it rotated in the oppositedirection one or more of the threaded Joints in the length of the stringof pipe may be loosened. This may result in separation of the pipestring so that a portion of the length of pipe and the tool carriedthereby will be lost in the well bore, requiring a fishing operation.This result may take place when manipulating tools of various kinds suchas packers, formation testers, well jars, and liner hangers.

Other types of devices have been designed to be operated, for lockingand setting in a well, by longitudinal movement of the pipe string.Devices of this type can be lowered to any desired point in the well andthen, by appropriate longitudinal movement of the pipe string can be setor locked in position in the well pipe. They can also be released by alongitudinal movement; but after such a release, unless twist is appliedthrough the pipe, they can only be moved in the casing in the directionin which the pipe string has been moved to release them. They cannot,after release, be moved in the opposite direction, either for removalfrom the well or for resetting in a position in that last mentioneddirection without applying twists through the pipe. Thus, to take aspecific illustration, it may be supposed that a liner hanger has beenset by one of thesedevices in a certain position in the casing. When setto support the liner hanger, the devices may be released by pullingupwardly on the pipe string, and thereafter the device may either bemoved upwardly out or the well or may be moved upwardly to a newposition where it may be reset. But, after having once been set andreleased, it cannot be moved downwardly to a new setting positionwithout pipe twist in one direction. And then, having reached the newlower setting position, the pipe must be twisted in the oppositedirection in order to effect the re-setting. The direction of one or theother 01 those twists is 5 Claims. (or. lee-#12) dangerous. And, to takeanother illustration, if such a device is used, in a relativelyvertically reversed position, to set and look a plug in a well to resistupward pressure, that device can then be released by downward movementof the drill string, but it can then only be moved downwardly in thecasing to a new setting position; and it cannot then be moved up to bere-set or to be removed from the well without applying twists throughthe pipe.

It is among the objects of the present invention to provide a lock andrelease device for holding a tool in any selected position, which devicepermits of operation for both locking and releasing solely bylongitudinal movement of the pipe string without requiring anyrotational movement; and which device further provides for releaseoperation and subsequent movement of the device in either direction inthe well casing, for resetting in any new position, or for removal fromthe well. The present invention contemplates a lock and releasestructure which may be associated with any desired type of oil well toolor any similar mechanism, in which one tool element is held relativelystationary while another tool element moves in relation thereto asmanipulated by the string of pipe, and between which tool elementslocking means are provided which act for locking and releasing solely bythe relative direct longitudinal movement of the movable tool elementwith relation to the temporarily fixed element.

One typical use to which the present invention ing drawings the toolwill be illustrated and described in its form as adapted for that use,but without any limitation thereto.

The invention is thus illustrated by way of example in the accompanyingdrawings in which:

Fig. l is a longitudinal vertical section, with parts in elevation,showing my lock and release device, in an illustrative form as used forthe setting of a liner; this figure showing the parts of the device inthe relative positions which they assume when being lowered through thecasing;

Fig. 2 is a fragmentary enlarged view in elevation illustrating therelative position taken by certain parts of the tool preliminary tobeing lowered into the casing;

Fig. 3 is an enlarged view in side elevation showing the lock andrelease device of the present invention, with the parts in the positionsassumed when the tool is being lowered in the casing, which is shown insection;

Fig. 4 is a view similar to Fig. 3 showing the lock and release iievicewith its parts in the relative positions assumed when the device is setand locked;

Fig. is a fragmentary elevation showing a modified form of the lock andrelease device: and

Fig. disacrosssectiononline Hofl'ig. 1.

Referring more particularly to the drawings, II indicates the lowerJoint of the string of pipe which is used to lower the devices into thewell and to manipulate them therein. As illustratively shown here, asetting sub H is attached to the pipe at the threaded Joint it. As hereshown the sub l I has, for instance, a depending wash pipe II fixedlyattached to its Joint member ll. The wash pipe extends through a tubularsection II, which is a part oi the setting sub. The lower end or thistubular section II is externally threaded with a left-handed thread atIt and has a counterbore l'l at the lower end of its central bore l Ithrough which wash pipe it passes. Packing It, held in place incounterbore II by a threaded nut ll, makes a fluid-tight joint betweenmember II and wash pipe IS. The lower end of wash pipe I! is equipp dwith an upwardly shouldered collar Ila which limits the upward movementof II in I l, and to which certain parts (not shown) oi a liner andwasher combination are attached. Tubular member II is formed with alongitudinal slot 2 I open at its upper end. This slot accommodates alug 22 projecting from wash pipe I I. The arrangement permits the washpipe to have a limited longitudinal movement with relation to sub-memberII and with relation to the parts carried by that sub-member, but at thesame time provides that wash pipe I3 and sub-member l I will rotatetogether.

An upper packer collar 28 is threaded at it left-handedly onto the lowerend of sub-member II. The upper end of a tube 28 projects into and issecured to collar 23. A suitable expansive packing ring or sleeve 2!surrounds tube 28 and lies between upper collar 23 and the uppershoulder of an annular expanding cone 2! which is free to move on sleeve25 and which compresses and expands packer 28 by moving upwardly.Downward movement 01' cone 2! is limited by a shoulder or ring 28 fixedon tube 25. The outer surface oi cone 2'! is tapered downwardly andforms the expansive surface for a set of vertically movable casing slips19. These slips are carried at the upper ends of spring arms 80. thelower ends of which are secured to a ring II which, in'

this form. oi the device, is formed as an upper portion of a cam sleeve3.

Cam sleeve II is freely mounted upon tube II, being free to slide androtate with reference thereto under control of the camming mechanismwhich will be described. The sleeve carries a set of bow springs 3!which frictionally engage well casing 32. These springs are secured attheir lower ends on sleeve 31 by rivets or screws 35, their upper freeends extending through a strap 3. on sleeve 33. The springs are sodesigned that they will i'rictionally engage the well casing and tend tohold sleeve 33 stationary whenever the device is raised or lowered inthe casing. In other words, they constitute a frictional drag which,during certain operations hold sleeve it relatively stationary.

The lock and release means which is now about to be described is a meanswhich, in this particular form of the device, acts between tube 25 andsleeve 33. to enable packer 2i and slips 2. to be set and locked, to beunlocked and released, and to be reset in any position which maysubsequentlybedesiredortoberemovedfromthehole.'I'heoperationofthislockandreleasedeviceis effected exclusively fromrelative longitudinal movement between cam sleeve II, and tube II or anyequivalent member which is connected to the pipe string. It. In thepraticular illustrative organization here shown, tube ll extends ondownwardly below the lower end of cam sleeve 83 to carry the variousparts which make up a liner. Patent 2,318,167, issued May 4, 1948, to L.R. Knowlton, shows the whole organization of a liner setting and washingdevice such as is contemplated in Fig. 1 of the present drawings. Insuch an organization wash tube I3 is extended on down through tube "bywash tube extensions which depend from collar I is: and the purpose ofthe limited longitudinal motion which is allowedbetween wash tube It andsub-member II is to allow of the vertical manipulation of certain partscarried by the extended wash tube, after tube 25 has been set inposition by operation of slips It and expansion of packer I. And in sucha complete organization, after the liner has been set and the washingoperations completed, then by right-handed rotation of pipe string IO,the lefthanded thread joint at I may be broken and disconnected and thewhole sub, including the part it, and all of the parts attached to washtube It. may then be removed from the well, leaving the liner in its setposition.

However, the particulars of the foregoing operations are not pertinentto the present invention; and the operation of my lock and releasedevice may be considered as it a pipe string II were directly, andeither releasably or non-releasably, connected to collar 23 and thus totube 25 or its equivalent. In the organization as here shown, the weightof the several parts which depend from wash tube II is sumcient to keepsub-member i5 .0 in its illustrated relative lowermost position on washtube It throughout the operations hereinafter described. In other words,although the drag of springs 34 is sumcient to hold cam sleeve is fromdownward movement while tube 26 is moved downwardly through it, the dragof those springs is not suillcient to causewash tube II to movedownwardly in sub-member ll. Thus, in the following described lockingand releasing operations which involve relative longitudinal movementbetween tube 25 and cam sleeve II, tube 25 and drill pipe ll may belooked upon as moving longitudinally as a unit. Or, in any case, thelooking and releasing operations which are to be described areoperations which are caused by relative longitudinal movement betweentube 2| and sleeve 33; and whether or not there may be some longitudinallost motion between pipe string Ill and tube 25 is of no consequence inthe operation of the locking and releasing device.

In the particular form shown in Figs, 1, 2, 3. and 4, the lock andrelease mechanism includes a lock pin 31 mounted on and extendingradially from the outer surface of tube 2'. This pin extends outwardlyinto a cam slot, generally desig- 'nated by the numeral 38, which slotis in this case out through the wall of sleeve 33. A modification willbe described later in which the locking pin is carried by sleeve 33 orits equivalent and the cam slot is formed in tube II or its equivalent.

The cam slot structure is designed to cooperate with pin 31 to permitsleeve 33 to be locked against movement, to be thereafter released ifdesired, and to be again locked if desired, so that the device may bemoved and set in any number of diiferent locations. Referring moreparticularly to Figs. .3 and 4 where the cam slot is shown at largerscale than in Fig.1, it will be seen in the particular cam formationhere illustrated that the slot has a vertically extending longitudinallane 33, here shown as straight and bounded on one side by a straightface 46 and on the other side by a straight face 4|. The upper end offace 40 terminates in a shoulder 42 which forms, with a wall 63. apocket C which lies directly above the upper end of lane 39of the camslot.

The lower, end of lane 39 is formed with a pocket D to which an inclinedcam face 44 leads;

so that pocket 43 is displaced from, a position directly under thevertical lane 39; in he particular illustration herein this displacementis shown pocket B is formed preferably lyi directly under the lower endof cam slot lane 6?? Pocket B lies at a definitely higher elevation anpocket D;

in fact, as will appear pocket D need have no definite closed end. Thelower lane 6 is formed between face 43 and relatively short face 6!which is here shown as lying in line with and, in effect, as a downwardcontinuation of face 66 whic forms the outer wall of the slot lane 61.Prefer- 5 ably. however. instead of faces 66 and 5! being continuous, anoffset pocket A is formed as illustrated by an inclined face 62, anupper curved face 63, and an upper inclined face 64. A tongue 55overhangs pocket A as illustrated.

The relatively long longitudinal face 66, which forms the outer wall ofslot lane 61, extends upwardly and merges with an inclined face 61 whichleads to the upper pocket C.

The internal defining faces of some of the cam slot lanes, including theface 4| which has been previously referred to, are formed by the edgesof an internal cam element 69. This element-has a face 66 which liesopposite face 66, and a face 6| lying opposite face 51. Face 6| mergesthrough curved end face 62 into face 4|. Faces .51 and 6| form betweenthem an upper inclined portion61b of the slot lane 61 leading to theupper pocket C. The lower end of face 60 merges into an inclined face 63which terminates, preferably through a curved shoulder portion 64 at thelower end of longitudinal face 4|. The cam element 69 is supported inposition by the strap 36 and another strap 65.

Attention is directed to the fact that pocket C, to which slot lane 61,61b leads, is in such a position above the upper end of slot lane 39,that when pin 31 moves relatively downwardly from pocket C it will enterthe upper end of lane 39. Attention is also, directed to the fact thatthe lower pocket D is out of vertical alinement with the lower end ofslot lane 39, so that the shoulder 64 overhangs pocket D. Or. in otherwords, the lower end 39a of slot 39 is inclined in such a manner thatpocket D underlies shoulder 64. With this arrangement, when pin 31 movesupwardly from pocket D it will move up into contact with shoulder 64 andinclined face 63 and be deflected through the cross passage 10 into thelongitudinal slot lane 61 and thus to a position above pocket B whichlies directly below the lower end of 61. And then, pocket B is sorelatedto the lower endpf slot run 61 that, upon relative downward movement ofthe pin from 61 it will pass into pocket B, or upon relative upwardmovement from pocket B it will pass into 61. In operation of the presentinvention the structure is assembled asshown, with slips 29 drawn downto their retracted positions by lowering sleeve 33 on tube 26.Preparatory to insertion in the casing the sleeve is hung on pin 31 byengaging pocket A on the pin (see Fig. 2). In this position the weightof the sleeve and slips hangs on the pin while the device is beinglowered into the upper end of the casing. Then when the drag springs 34engage in the casing as the device is lowered, the sleeve and slips willbe relatively dragged upwardly to the position shown in Figs. 1 and 3,pin 37 passing down into pocket B a ong the inclined face 62. In thisposition of the p agts the bottoming of pin 31 in pocket B holds theslips down in their non-expanded positions. To reach that positionsleeve 33 and the slips have rotated slightly on tube 26, but thatrotation has put no appreciable rotary torque on the drill string.

When the structure has been lowered to the desired setting position inthe casing, the pipe string is then lifted, sleeve 33 being heldrelatively stationary. Pin 31 will move upwardly from pocket B, into andthrough slot lane 61, and then through lane 61b, and finally into pocketC. In this operation sleeve 33 again rotates slightly relative to tube26, but no appreciable rotative torque is put on the pipe string as thesleeve is free to rotate relative to 26, and relative to the casingexcept for the small drag exerted by springs 34. In pocket C the pin isin alinement with the upper end of slot lane 39, and upon subsequentdownward movement of the pipe string and tube '25 the pin moves downdirectly into lane 39. On continued lowering, the pin moves down lane 39and 39a, guided by inclined face 44 into pocket D. As the pin moves downin D below the level of B, sleeve 33 and the slips move relativelyupwardly.

The slips up and out on cone 28 to expand and grip the casing and toforce the cone relatively upwardlyto expand packer 26. In this positionof the parts pin 31 has preferably not reached a bottom position inpocket D; and it is immaterial how far below that pin position thepocket D extends.

If it is desired to release the slips to pull the whole device from thewell, or to move it up to a new setting position, it is only necessaryto pull up the pipe string. Pin 31 will then move up through lane 33aand through the cross connecting lane 16, guided by faces 64 and 63,into lane 61, and thence up lanes 61 and 61b into pocket C. When the pinmoves above the level of B the slips are released. If, after measuredmovement upward, it is desired to re-set the slips, it is only necessaryto move the pin string down, when pin 31 will again move down lanes 39and 39a into pocket D.

If it is desired to release and re-set the slips in a relatively lowerposition, the pipe string is first moved up just far enough to carry pin31 up into lane 61 or 61bnot far enough to allow the pin to reachposition C directly over lane 39. Then, upon subsequent lowering, pin 31travels down lane 61 and down into pocket B; and the whole device thenmoves down the casin in the same condition as it did initially.Repetition of the initial setting operations will then re-set the '31 inpocket B) is not at all necessary. Straight longitudinal movements ofthe pipe string, without any rotation or torque strain on the pipejoints, perform the operations of setting, releasing and resetting.

It is to be particularly noted that, by proper manipulation of the pipestring, the device may be released and then moved in either direction,up or down, to a re-setting, or out of the well. Consequently, to usethe device as an anchor to take upward pressure instead of downwardforce it is only necessary to arrange the whole device on the pipestring in a position upside down, as related to the position of Fig. l,and then to operate it by movements which are relatively the opposite ofthose described above. And in such use it will be noted that the devicecan be released and moved in either direction to be re-set or to bepulled out of the casing.

The specific form of device so far described has the cam slot formed inor on the anchor sleeve 33 and has its pin 31 on tube 25 or otherequivalent part which is attached to the pipe string. That arrangementmay be reversed, as shown in Fig, 5.

There a pipe string 10c is shown directly attached to expanding cone23c, and tube 250 is shown as depending from pipe illc. Slips 29c,riding the cone upwardly to expand, are mounted on spring arms 30cattached to an upper ring 3lc. Drag springs 340 are mounted betweenspaced rings 3lc and 3ld which are free to move on tube 25c except ascontrolled by the cam device. The two rings and their interconnectingdrag springs form, in effect, a movable sleeve like 33 of Fig. 1. Pin310 is mounted on ring 3ld to project inwardly into a cam groove 380which is sunk in the outer face of tube 25-not necessarily cut throughits wall. Cam groove 380 is exactly like cam slot 33 except that it isrelatively reversed in a vertical direction. For use as a weightsupporting anchor the operational movements of this form are the same asfirst described for Figs. 1-4.

The major parts of groove 380 are indicated by references correspondingto those of Figs. 1-4

with the suflix c subjoined.

The following general observations will assist in an understanding ofthe essential features of the device and also of the scope of theinvention as defined in the following claims. In the foregoingdescription it has been assumed that pin 31 moves substantially to thebottom of the Docket at D when slips 29 are fully expanded against thecasing. In practice, the slips will preferably be fully expanded beforethe pin reaches the bottom of that pocket in order to insure fullexpansion of the slips. Or, to put the matter the other way around, thepocket or passage bottom shown at 45 may be located any suitabledistance below the pin position shown at D in Fig. 4; in fact, it isimmaterial whether there is any bottom or closed end to the passagebelow position D, as the setting of the slips determines the position towhich pin 31 will move down. And it is only necessary that the wholedevice be so proportioned and arranged that, in the set position of theslips, pin 31 has moved down the inclined wall 44 far enough that thepin is then under deflection shoulder 64 so that on subsequent straightupward movement the pin will be deflected by 64 and 63 into slot 31.

It has been mentioned before that pin 31 may be carried by the outersleeve 33 and the cam slot may be cut into the outer face of tube 25; in

which case the cam slot will be relatively inverted but will have thesame functions as here described. Thus, the whole anchor and lockingcombination comprises two members, one of which (here the tube 23) ismovable vertically with the well pipe (whatever that wellpipe may be)and the other of which (here the outer sleeve 33) has a draggingengagement with the well casing. These two members, respectively, carrythe two elements of the device to be operated (here the cone 21 andslips 23 of the anchor) which is operated to set and unset by relativevertical movement. One of the two relatively vertical movable memberscarries the pin which plays in the cam slot carried by the other ofthose two members. It is immaterial which one of the members carries thepin and which one carries the cam slot; the configuration of the camslot being the same in any case, except to be reversed vertically. Andit will also be readily understood that the whole combination device, ineither form shown in the drawings, can be turned upside down to anchor apipe or other unit against upward movement. However, for purposes ofsimplicity and clarity, this discussion of the whole device andparticularly of the functions of the cam slot are confined, withoutlimitation, to its operation in the form and orientation shown in theFigs. 1-4.

Starting with the pin in position B, where it is whenever the device isbeing lowered in dragging contact with the casing, it is only essentialthat when the pin moves up from position B it will travel up throughlane 61 so that it can be deflected by the upper diagonal wall 51 into aposition over the upper end of lane 39, or into a posi. tion from which,on subsequent downward movement, the pin will move down at the righthand side of the point 62 so as to enter lane 33 rather than to re-enterlane 31. Thus, if for the moment we disregard pocket A, the path whichlane 51 takes from pocket B to pocket C is of no particular importanceexcept that the upper end of lane 61 shall lead diagonally laterally (tothe right as illustrated) to guide the pin to a position C which islaterally past the point 62. Then, with reference to the movement of thepin downwardly from the position C, it is only necessary that, the pinhaving passed down to the right of point 32, the walls 4| and 40 be ofsuch shape as to guide the pin downwardly into and through lane 33.

With regard to lane 33, it is only important that it have a guiding wall44 which inclines downwardly and laterally toward lane 61 (in theparticular arrangement shown in the drawings to the left) to guide thepin laterally under the deflection shoulder 64 as the pin reaches orapproaches the position D. It is only essential that lane 39 and itsdownward diagonal continuation be such that upon subsequent upwardmovement of the pin from position D-it will move upwardly intoengagement with deflection shoulder 64 and be guided upwardly andlaterally again into lane 61, rather than move upwardly into lane 39.And. the pin having been deflected by shoulder 64, 33 into lane 31 it isthen only necessary that wall 56 of that lane be of such configurationand so placed that subsequent downward movement of the pin will carry itinto-position B. In other words, it is only necessary that deflectionshoulder 64 and 63 deflect the pin far enough to the left that, uponsubsequent downward movement, it will pass to the left of tongue 50.

From what has been said, it will be readily recognized that it is notnecessary for lanes 39 and 61 to be straight, or vertical or parallel,although in practice such configurations are preferable. And, as regardsthe pocket A which is initially hung on the pin as the device is loweredinto the casing, it is only necessary that that pocket open into lane 61at some point in one of its walls where the pin on moving down from A,will eventually move behind (to the left of) tongue 50 which defines theright-hand side of pocket B; and also that pocket A be so located withreference to slot 61 that the pin on its upward movement from B willpass up into 61 rather than into pocket A. For reasons such as these, astraight vertical run of slot 61 above pocket B is preferred, but notnecessary.

While I have shown the preferred form of my invention as now known tome, it will be understood that various changes may be made incombination, construction and arrangement of parts by those skilled inthe art, without departing from the spirit of the invention as claimed.

I claim:

1. In lock and release mechanism for well devices of the type whichembody two members one of which is longitudinally movable by controlfrom the ground surface and the other of which is movable bothlongitudinally and transversely with relation to the one, the secondmentioned member being provided with means for creating a frictionaldrag on the wall of the well tending to hold that member stationary, oneof said members being provided with a cam slot and the other with a slotengaging pin; the improvement in slot formation which comprises thecombination of two longitudinally extending and laterally spaced slotlanes joined together at one of their corresponding longitudinal ends,one of said lanes having a closed opposite end and that lane having arun approaching and entering the end junction in a diagona1 directionlongitudinally and laterally toward and into that end of the other lane,so that when the pin has passed through the first mentioned lane intothe joined end of the second mentioned lane by relative movement in onelongitudinal direction it will then pass through the second mentionedlane when the pin is moved longitudinally in the opposite direction withrelation to the cam slot; the other end of the second mentioned laneextending longitudinally, in the direction away from the joined ends,beyond the corresponding closed end of the first mentioned lane, thesecond mentioned lane having near its second mentioned end a diagonalrun leading longitudinally away from the joined ends and laterallytoward the first mentioned lane; and a crossconnecting lane leadingdiagonally from an intermediate part of the second mentioned lane intoan intermediate part of the first mentioned lane and longitudinallytoward the joined ends of the lanes. said diagonal lane having adiagonal pin-deflecting wall which laterally overhangs the secondmentioned end of the second mentioned lane so that when the pin .moveslongitudinally away from that end it will be engaged by said overhangingwall and deflected' into the intermediate part of the first mentionedlane.

2. The improvement specified in claim 1, and also including a pinreceiving pocket in the form of an extension from one side of the firstmentioned slot lane extending diagonally from that side in alongitudinal direction toward the joined ends 01' the two lanes.

3. The improvement specified in claim 1, and in which the first andsecond mentioned slot lanes extend longitudinally and are mutuallyparallel except in their diagonal runs, and also including a pinreceiving pocket in the form of an extension from that side of the firstmentioned lane which is opposite to the second mentioned lane, saidpocket extending diagonally from said lane in a longitudinal directiontoward the joined ends of the two lanes.

4. In lock and release mechanisms for well devices of the type whichembody two members one of which is longitudinally movable by controlfrom the ground surface and the other of which is movable bothlongitudinally and transversely with relation to the one, the secondmentioned member being provided with means for creating a frictionaldrag on the wall of the well tending to hold that member stationary, oneof said members being provided with a cam slot engaging pin and theother with a cam slot composed of two longitudinally extending andlaterally spaced lanes joined together at one of their correspondingends, one of the lanes being longitudinally shorter than the other inits extent from the joined ends; the improvement which comprises a pinreceiving pocket in the form of an extension from one side of theshorter lane extending diagonally from that side in a longitudinaldirection toward the joined ends of the two lanes.

5. In lock and release devices for well mechanisms which include asupporting member longitudinally movable from the ground surface, atubular member telescoping thereover and capable of longitudinal androtational movement rela tive to said supporting member, and meanscarried by said tubular member for creating a frictional drag on thewall of said well tending to hold said tubular member stationary as itis moved longitudinally in the well on said supporting members; anengaging element carried by one of said members, a cam slot formed onthe other of said members and receiving the engaging element, said slotcomprising a releasing lane and a setting lane, said lanes converging attheir one end and there terminating in a junction abutment adapted to beencountered by the engaging element, the releasing lane being formed atits opposite end with an abutment to be encountered by the engagingelement, said setting lane being formed at the opposite end from thejunction abutment with an extension passageway continuing longitudinallyof the tubular member a distance from the junction abutment greater thanthe distance of the releasing lane abutment from the junction abutmentand being offset laterally toward the releasing lane, a transverse laneestablishing communication between the releasing lane and the settinglane intermediate their ends, said transverse lane defining a path oftravel for the engaging element from the setting lane to the releasinglane in a direction toward the joined ends of said lanes, a divertingshoulder at the juncture of the setting lane and the transverse lane forguiding the engaging element from the extension end of the setting laneinto the transverse lane, and a diverting shoulder at the juncture ofthe joined ends of the releasing and setting lanes for directing theengaging element from the junction abutment into the setting lane.

. JOHN T. PHIPPS.

